In my experience suspensions of play have been treated much like the lunch breaks between rounds. You can throw discs without being considered practice; in fact, after a long delay, almost everyone practices putts before the resume of play. I'd think drinking would be the same.

The post about a tournament being resumed on another date isn't entirely out of order. I've had a Saturday afternoon round suspended until Sunday morning. It's a tough argument that substance prohibitions, dress codes, or any other PDGA rules applied during that time. "Rain delays" are usually for an indefinite time, and though the rulebook may not specify that these rules are suspended along with the play, I can't imagine, as a TD, enforcing them.